Concept and Illustration by Artur Ovanesyan, Raivix
Attention and learning is a currency in the world of product design and user experience. Users that have to “spend” less attention will stay in an experience longer. This attention and learning currency has a name: cognitive load.
While many designers focus on the aesthetic or visual appeal of their interface, a lot of UX issues stem from cognitive load – the amount of mental effort it takes to understand the content or function at hand.
As Steve Krug points out in his book Don’t Make Me Think, “users don’t want to think more than they have to.”Too much cognitive load can result in user frustration, errors, and abandonment. So how can we reduce the mental work without compromising usability?
1. What exactly is cognitive load?
Cognitive load is the amount of mental effort required to process and understand information. When cognitive load is high, it can lead to errors, poor decision making, and reduced efficiency.
Understanding cognitive load is understanding how the brain processes information. Our brains are constantly trying to make sense of the world around us by creating mental models. These models are based on our past experiences and understanding of the world. When we encounter something new, our brains try to fit it into one of these existing models. If it doesn’t fit, we have to adapt and accommodate for this new information.
Cognitive load isn’t just a blanket term, it comes in three different varieties of mental strain.
Intrinsic cognitive load
Intrinsic cognitive load is the amount of mental effort required to understand and use a piece of information. This type of cognitive load is inherent to the experience at hand. If users are coming across new material in the experience, intrinsic cognitive load may be unavoidable but managing is possible.
Extraneous cognitive load
This is the mental effort required to deal with non-essential elements of the task. For example, if the font size in a document is too small, it will take users out of the experience and focus on reading rather than scanning the words.
Germane cognitive load
This is the mental effort required to process and learn new information. For example, when you’re learning a new concept in school, the germane cognitive load will be high.
To reduce cognitive load and improve user experience, designers need to focus on minimizing extraneous and germane cognitive loads while also taking into account the intrinsic cognitive load of the task at hand.
2. Ways to reduce cognitive load
Help short term memory recall
Identify the information users would struggle to recall. There are subtle ways to do this. Show what has been liked, previously clicked on, and interacted via visual design. Limit the burden put on the users’ working memory.
Use clear and concise language
Every product will be built upon content. Users should be able to quickly scan the content and grasp the main points. Chunking information (packaging large pieces of information into smaller pieces of information) and using clear headings can help achieve this. In other words “keep it sesame street simple”
Assist with visuals when appropriate
Visuals can help the “scanability” of a user experience. Visuals can do their job if they are universally understood iconography and/or they have text to contextualize them. Use visuals to supplement text and help users grasp concepts more easily.
Clean user interface
The user interface is the crystallization of the user’s mental models. The more it is aligned with your users expectations and how they navigate through information, the less cognitive load will slow them down.
By starting with these guidelines, you can create user experiences that are easier for users to understand and navigate, which will ultimately lead to better overall performance.
3. How to measure cognitive load?
Measuring cognitive load is a tricky endeavor. It’s a subjective process since everyone has different cognitive thresholds. The most common test is the NASA Task Load Index (NASA-TLX). It looks at how information is being processed on six different levels
- Mental demand
- Physical demand
- Temporal demand
- Frustration level
This approach is time consuming and requires a researcher with a strong command of cognitive load theory.
An unconventional approach is having the user perform a mindless task, tapping their foot for instance, while completing an action in the user experience. If they cannot juggle understanding the UX while performing the mindless task, this could be a sign of the brain struggling to navigate the UX.
Some of the best cognitive load feedback are customers who’ve churned. If possible a survey or interview can reveal potential moments that were too difficult or frustrating. Regardless of cognitive load discoveries, these former customers are a wealth of potential growth for an organization.